Electric vehicles are coming into increasing importance because of their supposedly low environmental impact. When a heavyweight vehicle such as a truck or bus is fitted with an electric drivetrain driving the drive wheels through a speed reducing differential and one or more axles, it has been found that acceleration from low speeds is not smooth. Analysis of the perturbations in acceleration have shown that the stiffness of the axle shafts which couple torque to the drive wheels is such that the axle tends to twist, which, in conjunction with the very low friction of the electric drive train, results in oscillations of the vehicle speed.
Smoothly accelerating electric vehicles are desired.